[Ada] Hang on compilation of unit with type extension in body

gcc/ada/

	* exp_util.adb (Ancestor_Primitive): Prevent return of an
	subprogram alias when the ancestor primitive of the alias is the
	same as Subp.

diff --git a/gcc/ada/exp_util.adb b/gcc/ada/exp_util.adb
index b0ea44a7f7b7786a8a00fdfd89314b75cdf19909..1bba0595741e215175d3b85fe396c8753d331cce 100644 (file)
--- a/gcc/ada/exp_util.adb
+++ b/gcc/ada/exp_util.adb
@@ -10433,6 +10433,14 @@ package body Exp_Util is
          --  inherited ancestor primitive.
 
          elsif Present (Inher_Prim) then
+            --  It is possible that an internally generated alias could be
+            --  set to a subprogram which overrides the same aliased primitive,
+            --  so return Empty in this case.
+
+            if Ancestor_Primitive (Inher_Prim) = Subp then
+               return Empty;
+            end if;
+
             return Inher_Prim;
 
          --  Otherwise the current subprogram is the root of the inheritance or